Energy-efficient concurrent testing approach for many-core systems in the dark silicon age

Dark Silicon issue stresses that a fraction of silicon chip being able to switch in a full frequency is dropping and designers will soon face a growing underutilization inherent in future technology scaling. On the other hand, by reducing the transistor sizes, susceptibility to internal defects increases and large range of defects such as aging or transient faults will be shown up more frequently. In this paper, we propose an online concurrent test scheduling approach for the fraction of chip that cannot be utilized due to the restricted utilization wall. Dynamic voltage and frequency scaling including near-threshold operation is utilized in order to maximize the concurrency of the online testing process under the constant power. As the dark area of the system is dynamic and reshapes at a runtime, our approach dynamically tests unused cores in a runtime to provided tested cores for upcoming application and hence enhance system reliability. Empirical results show that our proposed concurrent testing approach using dynamic voltage and frequency scaling (DVFS) improves the overall test throughput by over 250% compared to the state-of-the-art dark silicon aware online testing approaches under the same power budget.